Does anyone know if it is illegal for a landlord to add damage to the move out inspection checklist after it was already signed by the tenant and landlord?

Also, is it legal for the landlord to enter the premises prior to the inspection time and start the inspection without the tenant present when the tentant hasnt signed the move out form? For example we walked in to our old rented property a few minutes prior to our inspection time to see our landlord had already been through the place and placed painters tape to all the marks on the walls. At that point we had still paid rent in full for that month and hadnt signed anything so we were still technically tenants of the property. He had also placed tape over damage that was from a previous tenant and tried to blame it on us.

Our landlord is nickle and diming us for every penny of our damage deposit it feels like. We were great tentants. Kept the place clean and spent 11 hours thoroughly cleaning the property prior to the inspection. Most damage was normal wear and tear minus a couple dings in the walls that happened during move in and move out. Hes trying to charge us $650 from our deposit for the repairs to the wall and paint. We even paid to get the carpets professionally cleaned upon move out even though they were pretty clean before hand. The ventilation sucked in the place and even though we used plastic shower curtain hooks and always used the ventilation system the curtain rod rusted which in my opinion is normal wear and tear. He wants to deduct $70 for a new curtain rod.